Clutch shifting linkage



Sept. 14, 1954 H. F. HEISLER CL'uTcH SHIFTING LINKAGE Filed March 2l 1950 5 Sheets-Sheet 2 Filed March 21. 1950 L/Ydr Bly Mg Sept. 14, 1954 H, F, HElSLER 2,689,031

I CLUTCH SHIFTING LINKAGE Filed March 21, 1950 5 Sheets-Sheet 3 fr! E. 3.

Sept. 14, 1954 H. F. HEISLER CLUTCH SHIFTING LINKAGE Filed Mabh 21, 195o 5 Sheets-Sheet 4 mw A Sept. 14, 1954 H. F. HElsLER 2,689,031

CLUTCH SHIFTING LINKAGE Filed March 21. 1950 5 Sheets-Sheet 5 15H/6,72 071' .,drry jf' ezfsler Patented Sept. 14, 1954 UNITED STATES PATENT' OFFICE CLUTCH SHIFTING LINKAGE Harry F. ,Hes1er, Hudson, Iowa.

Application March Z1, 195.0, Serial No. 150,852

4 Claims.. (Cl. 192-99) This invention relates to an overdrivev system and more particularly to an overdrive system which is easily adapted to existing transmissions of tractors and the like. The range of power speeds of farm tractors is very limited and the top speed of the usual power speed range is relatively low. For example, a typical tractor may have four power speeds ranging from 21A miles per hour to about 51/2 miles per hour. Tractors are also often equipped with a fth speed of about 18 M. P. H. which is attainable only when there is very little or no load on the tractor, and which speed is attained by connecting the drive shaft directly to the supply of power, thereby bypassing the countershaft. The tractors power speeds are designed low because the loads carried or hauled by tractors are usually very large and greater pulling power or torque is developed at lower speeds.

However, there are many occasions when the tractor is moving between jobs when it is 11nloaded or partially unloaded and higher power speeds are desirable. When those occasions arise, the tractor is unable to meet the demand for higher speeds, because of the low gear ratios which are available in the transmission` The high direct drive speed is often impractical if the tractor is partially loaded, or if the terrain over which the tractor is moving is rough. Thus it is desirable to provide intermediate power speeds having values between the highest of the existing power speeds and the high direct drive speed. While it is true that the entire transmission could be changed to give these higher power speeds, the high torque, lower power speeds would be lost in such an arrangement, which would be undesirable.

In adapting an overdrive system to an existing transmission it is desirable to retain as much as possible of the existing transmission. If possible, it is desirable to integrate the overdrive system with the existing shifting arrangement for thev transmission. The adaptation of an overdrive to an existing transmission without losing the original speeds of the transmission requires the use of additional shiftable members and means whereby the shiftable members are actuated. The proper use of such additional shiftable members is predicated, in some degree, upon a means for positioning and retaining the shiftable members in predetermined positions.

Thus, one of the objects of this invention is to provide a novel overdrive system for tractors which provides a range of higher speeds without sacricing the existing range of high torque lower speeds.

Another object of this invention is to provide an overdrive system for use within the transmis.- sion housing of the vehicle, which may be easily adapted to the existing transmission system,

A further object of this invention is to pro..- vide an overdrive system which is designed to be easily tted into the existing transmission housing for a motor vehicle.

A still further obo'ect of this invention is to provide a novel overdrive system, which converts an existing four speed transmission into an eight speed transmission, or an existing live speed transmission into a nine speed transmisE sion.

Another object of this invention is to provide a novel ball poppet means for positioning coe axial members, which are shiftable axially there, between, with respect to each other in a plurale ity of predetermined positions.

Still another object of. this invention is to provide a novel shifting means which consists of simple and inexpensive linkages lor use. with the novel overdrive system, which shifting means is easily adapted to the existing transmission structure.l

And still a further object of this invention is to provide a novel support means within the transmission housing tor performing the dual function of supplying a journal for a rock shaft oi the shifting means and for supporting a guide collar for the shitting lingers.

Further objects and advantages of this invention will become apparent as the following description proceeds and the features of novelty which characterize this invention `will be pointed out with particularitv in the claims annexed to and forming part of this .specication A preferred embodiment of the invention is shown in the accompanying drawing. in which- Figure 1. is a cross section side View of the drive shaft and the countershaft o f a typical transmission for a tractor, which have been modi,- ed to include elements of mv invention, and shoWS the shiftable clutch collar, mounted on the countershaft, shifted into the overdrive speed position.

Figure 2 is a top plan View, partly in cross section. of the countershaft and reverse gear shaft of a typical transmission `for a tractor, which have been modified to include elements of my invention, which view .is taken on. line zf-,Z of Figure 1.

Figure 3 is van end view partly in cross section of the transmission housing and the modified shafts and gears mounted therein and is taken on line 3-3 of Figure 1..

Figure 4 is a cross section view of one of the rock shafts in the overdrive shifting linkage and is taken on line 4-4 of Figure 3.

Figure 5 is an end view, partly in cross section, of the modied drive shaft and countershaft, showing the ball poppet means in more detail, and is taken on line 5.-.-5 of Figure 1- Figure 6 is another cross sectional end view of shaft is rotated at different speeds.

f the shafts and gears within the transmission housing, and is taken on line E-B of Figure 1.

Figure 7 is a top plan View, partly in cross section and partly in elevation with portions of the transmission housing broken away, of a portion of the overdrive shifting linkage and is taken on line '1 -1 of Figure 3.

Figure 8 is a side view of the part of the overdrive shifting linkage shown in Figure 7, and also shows the actuating rod for the shifting linkage. Figure 9 is a cross sectional View of the shiftable clutch collar mounted on the countershaft,

`showing the clutch collar shifted into the regular speed position. Figure 10 is a cross sectional view of the clutc collar and countershaft and is taken on line Figure 11 shows substantially the major parts `other than the shifting linkage that are supplied for adapting the overdrive system to the existing transmission. The view is similar to that in Figure 2, with the addition of the two gears `that are supplied for the drive shaft. These lat- `ter two gears are shown in Figure 11 rotated out vof vertical position, but positioned axially substantially as they would. be in the transmission housing. The parts in Figure 11 outlined in dot- `countershaft and a reverse gear shaft. The countershaft is journalled in bearings in apair of opf positewalls of the transmission housing. The reverse gear shaft is shorter than the drive shaft or countershaft and is supported at one point in one `wall of the transmission housing and supported at another point by a standard located in the `transmission shifting chamber, substantially in `mid-length thereof.

The drive shaft is journalled at one point in a bearing mounted in a wall of the transmission `housing and extends into the transmission shifting chamber. The other support for the drive `shaft is a bearing for the extended end of the drive shaft, which bearing is journalled within a .concentric recess of the power drive gear. The power drive gear itself has an extension shaft formed integrally .therewith and journalled in bearings in another wall of the transmission housing. Eiectively, the drive shaft is supported t by bearings in opposite walls of the transmission housing through the bearing joint in the recess of the power drive gear. l

This power drivel gear which is coupled to the source of power is in mesh with a single counter gear splined to the countershaft, whereby the countershaft is rotated when the power drive gear rotates. The bearing which, is at the end of the drive shaft, and is journalled inthe power drive gear recess, permits overriding of the power drive gear on the drive shaft.

Also non-shiftably splined to the countershaft are a pair of spaced double gears, each gear being of a different diameter and adapted to mesh with other gears on the drive shaft, whereby said drive One each of the two pairs of double gears correspond to speeds `referred to as rst, second, third, and fourth.

The gear that corresponds to second speed is in mesh with a first gear rotatably mounted on the reverse gear shaft.

The reverse gear shaft is iixedly mounted within the transmission housing. The rst gear on the reverse gear shaft is connected by means of a collar, rotatably mounted on the reverse gear shaft, to a second gear. gears and the collar rotate as a unit.

On the drive shaft are two single and one double shiftable gears. These gears are splined to the drive shaft, whereby the rotation of any one of the gears will result in the rotation of the drive shaft.

. All the gears are adapted to be shifted in opposite directions along the drive shaft. The nrst single gear is adapted to engage the gear on the countershaft corresponding to first when shifted in one direction and to engage the second gear on the reverse gear shaft when shifted in the opposite direction. The engagement with the second gear on the reverse shaft results in rotationof the drive shaft in the reverse direction.

The double gear on the drive shaft is positioned between the spaced pair of ,l double gears on the countershaft. When the double gear is shifted in one direction, one of its gears engages the gear on the countershaft corresponding to second, and when shifted in the opposite direction, the otherv gear of the double gear meshes with the countershaft gear corresponding 'to third. Similarly, the second single gear on the drive shaft when shifted in one direction engages the countershaft gear corresponding to fourth.

This second single gear on the drive shaft is also provided with an internally splined recess whereby when it is shifted, in the opposite direction to that wherein the fourth speed gear was engaged, the internal splines engage the teeth of the power ydrive gear rotatably journalled at the end of the drive shaft, wherebyv a fifth speed is provided. The internalsplines on the second single drive shaft gear engage only a portion of the power drive gear edge. This is provided for by reducing the diameter of the power drive gear over the portion to be engaged. Then the portion of the power drive gear that is not re- `duced in `diameter engages the second single drive able gear is in mesh, all the other shiftable gears are disengaged.

Referring now to the modined form which incorporates the elements of my invention and as shown in the'gures, there is shown in Figure l, a .transmission housing, generally indicated at Ii) enclosing a transmission shifting chamber ll. Apowerdrive gear l2 is part of a double gear le integrally formed with extension shaft iii. The extension shaft I5 is journalled by bearing i8 in wall 20 of transmission housing lli. The power drive gear l2 has a recess 22 therein adapted to receive sealed bearing 24.

A drive shaft generally indicated at 2t is journalled at a region intermediate its ends by means of bearing 28 in wall 3U of transmission housing i0. Other support for drive shaft 2li is located at the extended end thereof and comprises bearing 24 which is secured to drive shaft l by means of bolt 32. Thus, the drive shaft 2t is effectively supported by bearings i3 and 23 in walls 20 and 30 0f transmission housing li) The first and second through the bearing ioint comprising bearing 24 in recess 22 of power drive gear I2.

The drive shaft 2,6 extends Vthrough wall 30 of the transmission housing into chamber 34 within the transmissionhousing. Mounted on the end of lthe shaft which extends into chamber 34 is a pinion gear 36 which is the power take-oit for the wheels of the tractor.

A countershaft 38 is shown rotatably mounted in bearings it and 42 which are respectively positioned in walls 2i! and 3U of transmission housing It. One end of countershaft 38 is provided with an attachment M which may be connected to a hydraulic system pump (not shown) so as to actuate the hydraulic system of the tractor. The other end of countershaft 3&- is splined as at is so as to provide means for driving the auxiliary take-oit which powers the attachments to the tractors.

As seen more clearly Figures 2 and 3, a new reverse gear shaft 48 is xedly mounted in supports 5i) and 52 within the transmission housing. Support 5i) is integral with wall 3a of transmission housing and support 52 projects into the transmission housing chamber about mid-way between walls 2i) and 30 of the ktransmission housing. A pin 54 extendsthroug-hsupport 2 and through reverse gear shaft 48 thereby fixing shaft 48' in positionin supports 5e and 52. The new reverse gear shaft 43 extends beyond support 52 as at 49 to provide a support for a'bracket as will be hereinafter described.

Referring back to the drive shaft and to the power drive gear, as shown in Figure 1, the power drive gear I'Z is reduced in diameter over a porf tion of the gear edge thereof as indicated at 58. The drive shaft 25 is provided with two single and one double shiftable gears. These gears are splined to the drive shaft 2s' and are rotatable therewith and are adapted to be shifted in either direction along the drive shaft 26. The first shiftable single gear 58 is adapted to engage the gear on the countershaft corresponding to first speed when shifted in one direction and to engage the reverse speed gear when shifted in the opposite direction. The double shiftable gear fili has two gear faces E2 and 54 thereon. Gear 62 is adapted to engage the second speed gear on the countershaft when the douh-le gear et is shifted in one direction, and gear till is adapted to engage the third speed gear mounted on the countershaft when the double gear de is shifted in the opposite direction. The second single shiftable gear 66 is adapted to engage the 4fourth speed gear when it is shifted in one direction. Each of the shiftable gears 53,' Eli, and dit are provided with grooves 59 therein-adapted to receive means (not shown) for shifting said gears. The means for shifting these'gears, provided in the original transmission, are. retained herein and are well known in the art.

The single gear 66 in the original five speed setup was provided with internal splines to engage the reduced portion 56 of the gear edge of power drive gear I2. In the modified form herein, a portion of the spline length of shaft 2'5 has been reduced in diameter to eliminate the splines and to provide a bearing surface as at 68. Mounted on the reduced ydiameter portion 63 of shaft 26 is a ball bearing 1li. A' secondr power drive gear 72 is mounted on the bearing 'i0 and, therefore, is rotatably mounted on shaftf2t. This second power drive gear 'I2 is provided with an internally splined recess 'I4 adapted to engage the reduced diameter portion 56 of the gear edge of power drive gear I2. A snap ring I6 acts to keep the two power drive gears constantly in mesh, so that they rotate as a unit. The shoulder 'I8 in shaft 2G acts to keep the hearing 'E0 axially restrained from movement along the shaft. The greater diameter portion of the gear edge of power drive gear I2 butts against the face of the second power drive gear 'I2 at the interface 80, thereby restraining the gear 'I2 from axial movement in the opposite direction.

The second power drive gear 'I2 has a reduced diameter portion 82 on its gear edge as shown in Figure l. The shiftable single gear 66 is provided with a splined internal recess 84 which is adaptedto engage the second power drive gear 'l2 over the reduced diameter portion 82 of its gear edge, when the shiftable single gear 66 is shifted to the left as seen in Figure 1. The larger diameter portion of the gear'edge of power drive gear 'I2 provides a bearing interface i6 against which the shiftable single gear S butts when it is shifted to the left as 'described above. This bearing interface 8d provides a stop for limiting the motion of gear t6 in the direction to the left as shown in Figure 1.

Referring next tothe countershaft 38, a first and second driven gear is shown in mesh with the first and second power drive gears. A first driven gear 8d is shown in mesh with power drive gear I2. This first driven gear 88 is rotatably supported on hearings 90, which are mounted on a reduced diameter section 92 of countershaft 38. A second driven gear 94 is rotatably mounted with respect to countershaft 3B and is in mesh with the second. power drive gear i2;

Splined to the countershaft 38 is a clutch cole lar 95 which is rotatable with countershaft 33 and is shiftable in an axial direction thereon. A bearing et mounted on the outer periphery of clutch collar 9c? is adapted to receive and support the rotatably mounted gear M. Also splined to countershaftv 38 are Ya pair of double gears ist and |62. Snap rings IM are adapted to engage the faces of double gears me and H32 to prevent their axial movementV along the countershaft 3. Gear I (i5 of double gear Iiii corresponds to a first speed and is adapted to be engaged by first shiftable single gearv Sii-mounted on drive shaft 2S. Gear |08 of double gear IGS corresponds' to the second speed gear and is adapted to receive gear 62 of shiftable double gear til mounted on drive shaft 2S. Gear Il@ of double gear H32 corresponds to third speed and is adapted to receive gear 54 of shiftable double gear et which is mounted on drive shaft 2t. Gear i I2 of double gear i552 corresponds to fourth speed and is' adapted to receive gear face di of the second shiftable single gear 66 mounted on drive shaft 2t.

As seen more clearly lin Figures 2 and 3, a pair of gears im and II joined together by a collar IIS are rotatably mounted on reverse gear shaft 48. Gear Ils is in mesh with the second speed gear on countershaft 33 which is gear i333 of double gear itt. The gear H5 is adapted to be engaged by the'shiftable single gear 58 which is mounted on drive shaft 26.

Thus far the gears and their relationship to each other have been described. The manner of driving the countershaft through the power drive gears will now be disclosed. Asset forth above, a clutch collar 95 is splinedgto shaft 38 and is shiftable in an axial direction thereon. One end of clutch collar QS has formed thereon a gear I29. The rst drivenigear S8 has formed to receive a rotatable member.

to the right which is the position shown in Figure 1. The first driven gear 88 is also provided with an enlarged recess r|26 which is of greater diameter than the gear and which is positioned between the splined recesses |22 and |24. YWhen gear |26 is positioned in recess |26, both the first drivengear 88 and the second drive `gear 9.4 are disengaged from clutch collar 96.

A ball poppet means for axially positioning the clutch collar 96 with respect to the drive shaft 38 is also provided and is best shown in Figures 1 and 5. ReferringV to Figure 5, a plu- These bores |28 are located in alternate crotches between the splines. The ball poppet means further `comprises a compression spring |30 positioned in `each bore |28, and a steel ball |32 mounted in.

each bore |28-adjacent the mouth thereof. These balls |82 are in engagement with the spring |39 in the bore |28, and are resiliently biased outwardly from bore |28.

The clutch collar 96 is provided with a plurality of arcuate grooves |34 located in the faces of the `splines of the clutch collar 96.

'Ihese arcuate grooves lie in planes perpendicular to the longitudinal axis of the clutch collar 96 and the `countershaft 38, and are adapted to receive the resiliently biased balls |32, whereby resistance to axial displacement by the clutch collar 96 and `the countershaft 38 is obtained. As shown in 3 Figure 1, these arcuate grooves |34 are provided in three planes to provide for the three positions of the clutch collar; the rst position, as shown in Figure 1, being with the gear |20 in mesh with splined recess |24, the second position being with gear |20 positioned in recess |26, and the third position being with gear |20 in mesh with splined l recess |22.

The mechanism for shifting the clutch collar 96 includes a bracket generally indicated at |36, best shown in Figures 2, 3 and 11.

|86 has a cap portion |38 which is split so that the cap |38 may be adjustably clamped on the extended end 49 of reverse gear shaft 48, by means of bolt |40. 'I'he bracket |36 has extending from the cap portion |38 an arm |42 which v has drilled therein a vertical bore |44 adapted Also extending from arm |42 is a collar |46 which is coaxially l positioned around the clutch collar 96. The collar 46 is spaced from the surface of clutch collar 96,

` so as to provide clearance between the two coaxial The bracket `rality of radially extending cylindrical bores |28 n `are provided in countershaft 38.

together by a shaft I5 which is rockably mounted within vertical bore |44 in arm |42. The arms l |48 and |50 extend on opposite sides of the clutch collar 96 and collar |46. A finger |52 is mounted at the extended end of each arm |48 and |56. The ngers |52 are oppositely facing and are poadapted to receive the pins |52. Arcuate bearing y f strips |56 are positioned in the circumferential groove |54 and receive the extended tips of fingers |52 in holes |58 therein, provided for that purpose. The collar |46 is provided with elongated slots |60 through which the fingers |52 pass to enter into lthe circumferential groove |54 in clutch collar 96. When the shaft |6| together with arms '|48 and |50 are pivoted, the fingers |52 are swung in substantially an axial direction relative to the countershaft 38. This axial motion of fingers |52 is transmitted through bearing |56, through the Walls of lgroove |64, to clutch collar 96, thereby effectuating a shifting of the clutch collar 96.

In order to pivot the arms |48 and |56V together with shaft |5| within bore |44, it is necessary to provide av control linkage, which is most clearly shown in Figures 2, 3, '7 and 8. The arm |48 is connected by a link |62 to a toggle member |64 mounted within the transmission shifting chamher enclosed within transmission housing |6. The toggle member |64 is affixed to a rock shaft |66, which is mounted in the wall of overdrive housing i0, as shown in Figures 2, 3 and 4. As shown clearly in Figure 4, rock shaft |66 passes through an axial bore |68 of an insert H8 positioned in a hole in the wall of transmission housing I0. The hole is formed by reaming out a tapped oil plug hole in housing i8. A pair of grease seals |12 are provided to prevent the leakage of grease or oil between insert |26 and the wall of transmission housing I0. A packing |'|4 is provided between rock' shaft |66 and insert |10 to prevent leakage of. oil past the face between those two members. A cap |716 is provided for keeping the packing W4 in position and is threaded to the extended end of insert il'l, whereby the entire insert assembly may be clamped together by tightening up on cap |26. A toggle member |78 is secured by means of set screw |86 to the end of rock shaft |66, which ex tends outside of the transmission housing 0.

passage therethrough in one direction by the toggle member |84 which is welded to the control rod |86. IThe control rod |86 is prevented from movement through the hole in the opposite direction by means of cotter pin |92.

It can be seen that by rotating the control arm |86, the linkage carries the motion through the rock shaft |66 through the linkages to the control arms |48. The arms |48 and |56 are swung through an arc, by means of rockshaft |5| which is pivoted within bore |44, to effectuate shifting of the clutch collar 96. l

A means for axially positioning the driven gears 88 and 94 with respect to the countershaft 32 is also provided as-shown in Figure 1. A ring |98 is positioned between bearing 90 and shoulder |96 on countershaft 38. lThis ring |94 positions the bearing 90 with respect to motion to the 1ieft. A snap ring |98 is mounted in an inner recess in first driven gear 88 and engages the bearing 66. rIhe iirst driven gear 88 and second driven gear 94 have a bearing interface 260 therebetween. In order to restrict the motion of second driven gear 94 in the direction to the right as seen in Figure l a pair of spacer rings 202 and 284 are provided on opposite sides of collar |46, with the spacer ring 204 being inserted in a recess in double gear |02, which gear |02 is fixed axially 4gaseosa relative to countershaft 38 `in the manner `described above. and shoulder let cooperating with snap ring 198, spacer rings 282 .and 284, collar v|46 and double gear H32 together clamp the driven gears and 9d in substantially non-movable positions axially, while driven gears 88 and 94 remainrotatably mounted with respect to countershaft 38.

Operation v In the operation of the transmission and overdrive, the first Vand secondpower drive gears are always in mesh and rotate as a unit. The first driven gear 88 and second driven gear dei are in mesh respectively with first power drive gear l2 and second power drive gear l2 and hence are always rotated. When the clutch collar 98 is in the position shown in Figure l, the first driven gear y88 is not rotating as fast as is the second driven gear ed. In the position shown in Figure 1, the second driven gear .fifi is splined through clutch collar et to countershaft 38, and the countershaft rotates with second driven gear trl. At that time the first driven gear 88 is underrunning the countershaft 38. To provide the various speeds for the tractor or vehicle, the transmission gears 58, @t and 66 are shifted as before and provide for different speeds.

When the clutch collar 96 is in the position shown in Figure 9, then the rst driven gear 33 is splined in driving connection to the countershaft 38 and the second driven gear 94 is overrunning with respect to the countershaft 38. The bearing surface 93 between the clutch collar $36 and the second driven gear 94 provides for ease of rotation. When in this position with the first driven gear in driving connection with the countershaft 38, there are still four more speeds available by shifting the gears 58, 68 and 66, into engagement with the gears mounted on and rotating with countershaft 38.

When the clutch collar is positioned so that gear l 29 is within the recess |26, then neither the rst driven gear nor second driven gear are in driving engagement with the countershaft 3B and hence countershaft 38 does not rotate. At that point, only one speed is available for the wheels of the tractor and that is obtained by shifting gear 66 in the direction where the internal splines 8G. in gear @t may engage the recessed gear edge t 82 of second power drive gear l2. In fact, even if the clutch collar 96 is in engagement with either of the two driven gears 88 or et, this speed resulting from the engagement of recessed gear edge 82 with internal splines 84 of gear 665 is always available.

Thus, it can be seen that I have provided a novel overdrive system for a motor vehicle, which overdrive system may be easily fitted into the existing transmission Ahousing and adapted to the existing transmission system therein, and which overdrive System preserves all the original speeds of the transmission besides providing a range of higher speeds, whereby for example an existing five speed transmission is converted into a nine speed transmission.

There have also been provided a simple and inexpensive shifting means, a novel support bracket for the shifting means adapted to be mounted Within the transmission housing, and ball poppet means for positioning shiftable coaxial overdrive members with respect to each other in a plurality of predetermined positions.

While there has been shown and described a particular embodiment of this invention, it will It can ybe seen that the ring 1.94

. 10 be obvious to `those skilled in .the `art that various changes and `modification may be made therein without departing from the invention and, therefore, it 'is intended in the appended claims to cover all such changes and modifications as fall within the true .spirit fand scope of the invention.

What I claim as new-and desire rto secure by Letters Patent o'f the United States is:

l. A shifting means for an overdrive clutch collar, which clutch collar is slidably mounted on a shaft and rotatable therewith, said clutch collar having a circumferential groove therein; said shifting means comprising a plurality of pins positioned within the circumferential groove and adapted to be moved axially of said shaft, whereby the clutch collar is shifted, said plurality of pins being symmetrically disposed about the center of rotatio-n of said clutch collar, a plurality of arms secured to a rock shaft and having said plurality of pins extending therefrom, limiting means positioned to engage said pins to restrict the range of movement of said pins, and a mounting bracket for said limiting means having journal means therein for said rock shaft.

2. A shifting means for an overdrive clutch collar, which clutch collar is slidably mounted on a shaft and rotatable therewith, said clutch collar having a circumferential groove therein; said shifting means comprising a plurality of pins positioned within the circumferential groove and adapted to be moved axially of said shaft, whereby the clutch collar is shifted, said plurality of pins being symmetrically disposed about the center of rotation of said clutch collar, a plurality of arms secured to a rock shaft and having the plurality of pins extending therefrom, means for pivotally mounting said rock shaft, and limiting means for restricting the range of movement of the pins, said limiting means including a collar mounted coaxially with and spaced from said clutch collar, means mounting said collar to fix it axially with respect to said shaft, and said collar having a plurality of elongated slots therein in which said pins are positioned, said elongated slots providing freedom for movement of the pins within a predetermined range.

3. A shifting means for an overdrive clutch collar, which clutch collar is slidably mounted on a shaft and rotatable therewith, said clutch collar having a circumferential groove therein; said shifting means comprising a plurality of pins adapted to be positioned within the circumferential groove and adapted to be moved axially of said shaft, whereby the clutch collar is shifted, said plurality of pins being symmetrically disposed about the center of rotation of said clutch collar, a plurality of arms secured to a rock shaft and'having the plurality of pins extending therefrom, limiting means including an axially fixed collar for restricting the range of movement of the pins, and a mounting bracket for said xed collar having journal means therein for said rock shaft.

4. A shifting means for an overdrive clutch collar, which clutch collar is slidably mounted on a shaft and rotatable therewith, said clutch collar having a circumferential groove therein; said shifting means comprising a plurality of pins adapted to be positioned within the circumferential groove and adapted tobe moved axially of said shaft, whereby the clutch collar is shifted, said plurality of pins being symmetrically disposed about the center of rotation of said clutch collar, a plurality of arms secured to a roel: shaft Number and having the plurality of pins extending therefrom, bearing means rotatably mounted in said circumferential groove and adapted to receive shaft.

References Cited in the file of this patent UNITED STATES PATENTS Name Date 959,878 Page May 31, 1910 Number 12 Name Date Neville Sept, 23, 1919 Gaylord Sept. 12, 1933 White Nov. 14, 1933 Roos July 24, 1934 Conley July 2, 1935 Peterson May 6, 1941 Margrave Mar. 30, 1948 Avila Mar. 15, 1949 Gustafson Oct. 25, 1949 Zwald Jan. 10, 1950 Neely Feb. 13, 1951 

